Volume 2 Issue 5 May 2017

Volume 2 Issue 5

Traffic control in silicon

Back-contacted silicon solar cells with interdigitated passivated contacts have high efficiencies but are complex to manufacture. Tomasi et al. now report a simple process to self-align the two types of electronic contacts based on the surface-dependent crystalline growth of silicon and fabricate solar cells with a certified efficiency above 22%.

See Tomasi et al. 2, 17062 (2017).

Image: Tomasi et al. Cover design: Alex WIng.

Editorial

  • Editorial |

    Disruption is often a bad word in established industries, and electricity generation is no exception. But with silicon solar cells getting ever closer to efficiency limits, innovative solutions are needed.

Research Highlights

News & Views

  • News and Views |

    The deployment of Li–air batteries is hindered by severe parasitic reactions during battery cycling. Now, the reactive singlet oxygen intermediate is shown to substantially contribute to electrode and electrolyte degradation.

    • Alan C. Luntz
    •  & Bryan D. McCloskey
  • News and Views |

    Oil and gas extraction via hydraulic fracturing is controversial, with government support but mixed public opinion. Deliberative research shows that securing public support may be difficult because citizens in the United States and United Kingdom are sceptical of government and industry motives.

    • Philip Macnaghten
  • News and Views |

    Silicon-based photovoltaics dominate the market. A study now sets a new record efficiency for large-area crystalline silicon solar cells, placing the theoretical efficiency limits within reach.

    • Pierre-Jean Ribeyron
  • News and Views |

    Multiple exciton generation, in which two electron–hole pairs are generated from the absorption of one high-energy photon, has been demonstrated to improve efficiency in quantum-dot-based solar cells. Now, a photoelectrochemical system using PbS quantum dots is shown to drive hydrogen evolution with external quantum efficiency over 100%.

    • Mikhail Zamkov

Review

  • Review Article |

    Publically funded energy technology research is critical for a successful low–carbon energy transition, but future uncertainty means decision–making is difficult. This Review explores the role of expert elicitations, integrated assessment models and decision frameworks in informing energy technology policy.

    • Laura Díaz Anadón
    • , Erin Baker
    •  & Valentina Bosetti

Research

  • Article |

    The efficiency of silicon solar cells has a large influence on the cost of most photovoltaics panels. Here, researchers from Kaneka present a silicon heterojunction with interdigitated back contacts reaching an efficiency of 26.3% and provide a detailed loss analysis to guide further developments.

    • Kunta Yoshikawa
    • , Hayato Kawasaki
    • , Wataru Yoshida
    • , Toru Irie
    • , Katsunori Konishi
    • , Kunihiro Nakano
    • , Toshihiko Uto
    • , Daisuke Adachi
    • , Masanori Kanematsu
    • , Hisashi Uzu
    •  & Kenji Yamamoto
  • Article |

    Fast ionic conductivity of solid electrolytes is a must in the development of next-generation solid-electrolyte-based lithium-ion batteries. Here the authors report that composite polymer electrolytes with well-aligned inorganic nanowires can achieve much larger conductivities than those without.

    • Wei Liu
    • , Seok Woo Lee
    • , Dingchang Lin
    • , Feifei Shi
    • , Shuang Wang
    • , Austin D. Sendek
    •  & Yi Cui
  • Article |

    The application of Li–O2 batteries is hindered by severe parasitic reactions in battery cycling. Here the authors show that the highly reactive singlet oxygen is the main cause for the electrolyte and carbon electrode degradation on discharge and charge.

    • Nika Mahne
    • , Bettina Schafzahl
    • , Christian Leypold
    • , Mario Leypold
    • , Sandra Grumm
    • , Anita Leitgeb
    • , Gernot A. Strohmeier
    • , Martin Wilkening
    • , Olivier Fontaine
    • , Denis Kramer
    • , Christian Slugovc
    • , Sergey M. Borisov
    •  & Stefan A. Freunberger
  • Article |

    Perovskite-based solar cells are often fabricated by methods that are not industrially scalable. Here, Yang et al. develop an ink formulation which gives similar devices by spin coating, the lab-scale standard, and blade coating, which is a more scalable, industry-relevant deposition method.

    • Mengjin Yang
    • , Zhen Li
    • , Matthew O. Reese
    • , Obadiah G. Reid
    • , Dong Hoe Kim
    • , Sebastian Siol
    • , Talysa R. Klein
    • , Yanfa Yan
    • , Joseph J. Berry
    • , Maikel F. A. M. van Hest
    •  & Kai Zhu
  • Article |

    Photoelectrochemical devices based on III–V semiconductors have high performance potential but their cost and stability inhibit their wide application. Kang et al. make printed assemblies of GaAs-based photoelectrodes with separate optical and reactive interfaces, demonstrating water-splitting efficiency up to 13.1%.

    • Dongseok Kang
    • , James L. Young
    • , Haneol Lim
    • , Walter E. Klein
    • , Huandong Chen
    • , Yuzhou Xi
    • , Boju Gai
    • , Todd G. Deutsch
    •  & Jongseung Yoon
  • Article |

    Multiple exciton generation has been shown to improve the performance of quantum-dot-based solar cells. Yan et al. now apply it to photoinduced hydrogen production and present a system using PbS quantum-dot photoelectrodes that yields an external quantum efficiency of over 100%.

    • Yong Yan
    • , Ryan W. Crisp
    • , Jing Gu
    • , Boris D. Chernomordik
    • , Gregory F. Pach
    • , Ashley R. Marshall
    • , John A. Turner
    •  & Matthew C. Beard
  • Article |

    Shale gas and oil production and prospective development are increasing, but methods for shale extraction (‘fracking’) have been met with opposition. This study shows that informed discourse around shale development focussed on risks or doubts about benefits in a similar manner across the US and UK.

    • Merryn Thomas
    • , Tristan Partridge
    • , Barbara Herr Harthorn
    •  & Nick Pidgeon
  • Article |

    The most efficient silicon solar cells use interdigitated back-contact silicon heterojunction architectures. Here, the authors fabricate this type of cell via a simpler process, using an interband silicon tunnel junction for the electron contact and reaching a certified efficiency higher than 22%.

    • Andrea Tomasi
    • , Bertrand Paviet-Salomon
    • , Quentin Jeangros
    • , Jan Haschke
    • , Gabriel Christmann
    • , Loris Barraud
    • , Antoine Descoeudres
    • , Johannes Peter Seif
    • , Sylvain Nicolay
    • , Matthieu Despeisse
    • , Stefaan De Wolf
    •  & Christophe Ballif